I am looking for a 400ex slip-on with alot of bottom end without losing any top end. What would you guys suggest to me? Also what would i have to jet my carburator to? I am lower than 500' above sea level

 

there s lots of them like hmf white bros e2 or the pro circuit t 4 not sure on jetting there but iam at 1200 ft. i run a 165 dyno jet in mine.

 

with the air box lid on, i would run a keihin 152-155 mainjet. also, screw the fuel screw out a 1/2 turn or so. by the way, i think i still have a white brothers R4 slip on forsale. it may be sold but i am not sure yet. if your interested, let me know.

 

I am partial to FMF. Either the PowerCore IV or the Titanium 4 are great mufflers (https://www.fmfracing.com/products/c...?CategoryID=13).

It's a waste of time to do a muffler without also doing your air INTAKE as well! I suggest a vented airbox lid (http://www.ehsracing.com/) and a better flowing air filter (http://www.unifilter.com/). Do it all at the same time, then you only have to rejet once.

Don't forgert that here in Calif., you cannot be louder than 96dB (which is still quite loud)! So, you will have to run a Quiet Core, and of absolutely a spark arrestor screen!

Where do your ride out there???

 

I ride mostly at Glamis, Ocotillo wells, and Gordons well

 

I also ride octillo wells and Glamis... Does the White Brothers run at 96 or lower, and do they come with a spark arrester?

 

i run a hmf on my 300ex, and it runs at 98.2decibles;you can get a quite core for $20

 

will it fit my 2003 400ex or not??
if so how much do u want for it and were are u located?
get back to me asap plz

 

Curtis Sparks is one of the best exhausts for a 400ex. Get that. White Bros. is just as good.

 

Is there any advantages to doing a whole exhuast system, versus a slip on?